<template>
  <div>
    <router-link
      tag="div"
      to="/"
      class="header-abs"
      v-show="showAbs"
    >
     <span class="icons"><i class="iconfont icon-fanhui-copy"></i></span>
    </router-link>
    <div class="header-fixed"
          v-show="!showAbs"
          :style="opacityStyle"
         >
        <router-link to="/">
          <div class="iconfont icon-fanhui"></div>
        </router-link>
      景点详情
    </div>
  </div>
</template>

<script>
export default {
  name: 'DetailHeader',
  data () {
    return {
      showAbs: true,
      opacityStyle: {
        opacity: 0
      }
    }
  },
  methods: {
    handleScroll () {
      const top = document.documentElement.scrollTop
      if (top > 60) {
        let opacity = top / 140
        opacity = opacity > 1 ? 1 : opacity
        this.opacityStyle = { opacity }
        this.showAbs = false
      } else {
        this.showAbs = true
      }
    }
  },
  activated () {
    window.addEventListener('scroll', this.handleScroll)
  },
  deactivated () {
    window.removeEventListener('scroll', this.handleScroll)
  },
  created () {
    window.addEventListener('scroll', this.handleScroll)
  }
}
</script>

<style lang="stylus" scoped>
@import '~styles/varibles.styl'
  .header-abs
    position absolute
    left .2rem
    top .2rem
    width .7rem
    height .7rem
    border-radius .4rem
    background rgba(0,0,0, .5)
    .icons
      position absolute
      left .15rem
      top .15rem
      i
        font-size .45rem
        color: #ffffff
  .header-fixed
    position fixed
    top 0
    left 0
    right 0
    z-index 2
    height $HeaderHeight
    line-height $HeaderHeight
    text-align center
    color #ffffff
    background-color $bgColor
    font-size .32rem
    .icon-fanhui
      position absolute
      top 0
      left 0
      width .64rem
      text-align center
      font-size .4rem
      color #ffffff
</style>
